gerard

Assistant Professor
Department of Sociology
Columbia University

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I am an Assistant Professor in Sociology at Columbia University and a member of the Data Science Institute. I use causal inference and machine learning methods to study urban inequality, violence, and racial disparities in policing. My work has been published in the American Sociological Review, Child Development, Demography, the Journal of Urban Economics, the Proceedings of the National Academy of Sciences, and Social Science & Medicine among other peer-reviewed journals. Findings from my research have been featured in The New York Times, The Washington Post, and Bloomberg. I received my PhD in Sociology from New York University in 2019, a Master’s in Public Policy from the Harvard Kennedy School of Government in 2014, and a BS in Engineering from the Polytechnic University of Catalonia in 2004. Before graduate school, I was a firefighter at Barcelona Fire Department from 2007 to 2011. In my free time, I enjoy running, cycling, and hiking.

 

News and Updates

• 01-2024: I am grateful for the opportunity to join the Russsell Sage Visiting Scholar Class of 2024–2025.
• 06-2023: The study “Understanding Why EmpaTeach Did Not Reduce Teachers’ Use of Violence in Nyarugusu Refugee Camp: A Quantitative Process Evaluation of a School-Based Violence Prevention Intervention,” co-authored with researchers from the Behavioral Insights Team, the International Rescue Committee, and the London School of Hygiene and Tropical Medicine, has been published in PLoS Global Public Health.
• 03-2022: The research that Sam Donahue and I are doing on the effects of diversity and peer influences in policing has been awarded a Trustee Grant from the Russell Sage Foundation.
• 01-2022: The article “Declining Violence and Improving Birth Outcomes in the US: Evidence from Birth Certificate Data,” co-authored with Nicholas Mark, has been published in Social Science and Medicine.
• 10-2021: The study “The EmpaTeach Intervention for Reducing Physical Violence from Teachers to Students in Nyarugusu Refugee Camp: A Cluster-Randomised Controlled Trial,” co-authored with researchers from the Behavioral Insights Team, the International Rescue Committee, and the London School of Hygiene and Tropical Medicine, has been published in PLoS Medicine.
• 02-2021: My article “Using Machine Learning to Estimate the Effect of Racial Segregation on COVID-19 Mortality in the United States” has been published at the Proceedings of the National Academy of Sciences.
• 07-2020: I started as an Assistant Professor in Sociology at Columbia University.
• 01-2020: My article “Crime and Inequality in Academic Achievement Across School Districts in the United States” has been published in Demography.
• 07-2019: I started as a postdoctoral researcher at Columbia University’s Data Science Institute.

Recent Publications

PLOS Global Public Health, 2023 (with Camilla Fabbri, Timothy Powell-Jackson, Katherine Rodrigues, Alexandra De Filippo, Michael Kaemingk, Baptiste Leurent, Elizabeth Shayo, Vivien Barongo, Karen M. Devries)

EmpaTeach was the first intervention to address teacher violence to be tested in a humanitarian setting and the first to focus on reducing impulsive use of violence, but a cluster randomised trial found no evidence that the intervention was effective in reducing physical and emotional violence from teachers. We aimed to understand why. We conducted a quantitative process evaluation to describe the intervention implementation process (what was implemented and how); examine teachers’ adoption of …
The decline in crime that occurred in the last decade of the 20th century was one of the most important societal changes in recent U.S. history. In this paper, we leverage the sharp decline in violence that began in the 1990’s to estimate the relationship between county-level murder rates and individual-level birth outcomes for Black, Hispanic, and White mothers. Using the FBI’s Uniform Crime Reporting data from 1992 to 2002 and individual-level data from more than 30,000,000 US …

PLoS Medicine, 2021 (with Camilla Fabbri, Katherine Rodrigues, Baptiste Leurent, Elizabeth Allen, Mary Qiu, Martin Zuakulu, Dennis Nombo, Michael Kaemingk, Alexandra De Filippo, Elizabeth Shayo, Vivien Barongo, Giulia Greco, Wietse Tol, and Karen M. Devries)

School-based violence prevention interventions offer enormous potential to reduce children’s experience of violence perpetrated by teachers, but few have been rigorously evaluated globally and, to the best of our knowledge, none in humanitarian settings. We tested whether the EmpaTeach intervention could reduce physical violence from teachers to students in Nyarugusu Refugee Camp, Tanzania. We conducted a 2-arm cluster-randomised controlled trial with parallel assignment. A complete sample of …
This study examines the role that racial residential segregation has played in shaping the spread of the novel coronavirus disease 2019 (COVID-19) in the US as of September 30, 2020. The analysis focuses on the effects of racial residential segregation on mortality and infection rates for the overall population and on racial and ethnic mortality gaps. To account for potential confounding, I assemble a data set that includes 50 county-level factors that are potentially related to residential …
This study investigates the effect of violent crime on school district–level achievement in English language arts (ELA) and mathematics. The research design exploits variation in achievement and violent crime across 813 school districts in the United States and seven birth cohorts of children born between 1996 and 2002. The identification strategy leverages exogenous shocks to crime rates arising from the availability of federal funds to hire police officers in the local police departments where …

Eastern Economic Journal, 2020 (with Ingrid Ellen)

Using restricted administrative data on the voucher program, we examine the experience of voucher holders in metropolitan areas with rising rents. While some of our models suggest that rising rents in metropolitan areas are associated with a slight increase in rent-to-income ratios among voucher holders, poor renters in general see significantly larger increases in rent-to-income ratios. We see little evidence that rising rents push voucher holders to worse neighborhoods, with voucher holders in …
The housing choice voucher program aims to reduce housing cost burdens as well as to enable recipients to move to a broader diversity of neighborhoods. Prior evidence shows voucher recipients still end up in neighborhoods with relatively high poverty rates and low performing schools. These constrained neighborhood choices can in part be attributed to landlord discrimination and the geographic concentration of units that rent below voucher caps. In this paper, we consider the role of information …
On the 50th anniversary of the Fair Housing Act, long-time residents of cities across the country feel increasingly anxious that they will be priced out of their homes and communities, as growing numbers of higher-income, college-educated households opt for downtown neighborhoods. These fears are particularly acute among black and Latino residents. Yet when looking through the lens of fair housing, gentrification also offers a potential opportunity, as the moves that higher-income, white …

Proceedings of the National Academy of Sciences, 2018 (with Laia Balcells)

This study investigates the consequences of terrorist attacks for political behavior by leveraging a natural experiment in Spain. We study eight attacks against civilians, members of the military, and police officers perpetrated between 1989 and 1997 by Euskadi Ta Askatasuna (ETA), a Basque terrorist organization that was active between 1958 and 2011. We use nationally and regionally representative surveys that were being fielded when the attacks occurred to estimate the causal effect of …